MCQ PracticePermanent hardness of water is due to the presence of calcium & magnesiumSubject: Chemical EngineeringTopic: Chemical ProcessABi-carbonatesBSulphates & chloridesCCarbonateDNone of theseCorrect Answer: BPractice QuizBack to MCQsRelated MCQsCurrent flows in a circuit whenEighttenths coulomb passes a point in 4 s. The current in amperes isThe unit of electrical charge is the